In vivo antiprotozoan effects of garlic (Allium sativum) and ginger (Zingiber officinale) extracts on experimentally infected mice with Blastocystis spp.

Controversy surrounding the pathogenic role of Blastocystis spp. in humans and lack of well-established diagnostic criteria led to debates concerning the treatment for that organism. Furthermore, some strains develop resistance against the recommended drugs. Thus, using natural medicine has many positive aspects to address these points. In an earlier study, we addressed in vitro effect of garlic and ginger on Blastocystis spp. isolates as an alternative treatment. Accordingly, this study was conducted to evaluate in vivo activities of these two herbs on mice infected with Blastocystis spp. Antiprotozoan activities were determined by monitoring Blastocystis shedding in stools and histopathological changes of the intestine of infected mice. Additionally, assessment of the antioxidant effect (via measuring the level of malondialdehyde (MDA) production) of these herbs on the treated groups of mice was done. Also, their effects on nitric oxide (NO) production were assessed. In this work, treatment of infected mice with garlic, ginger, and nitazoxanide (NTZ) reduced the shedding of cysts significantly compared to the infected untreated group, P value ≤0.001, 0.0001, and 0.0003, respectively. As well, histopathological examination revealed that Blastocystis was frequently observed within the lumen, at the tip of the epithelium, and/ or infiltrated in an enterocyte in the infected group without treatment compared to that of the infected treated ones. Furthermore, mice infected with Blastocystis exhibited increased levels of NO (440.09 ± 3.7 vs. 276.66 ± 0.8, P ≤ 0.001) and MDA production (106.19 ± 0.43 vs. 63.06 ± 0.45, P ≤ 0.0004) compared to that of the uninfected controls. Treatment of infected mice with garlic, ginger, and NTZ reduced NO levels to 54.41 ± 1.2, 47.70 ± 1.2, and 37.43 ± 0.98 and MDA levels to 22.38 ± 0.17, 63.34 ± 3.89, and 66.76 ± 9.1, respectively. We conclude that using ginger and garlic for treatment of blastocystosis is beneficial.